Interaction between migrating (10(1)over-bar2) twin boundary and extended < a > dislocations inside twin in pure Mg

Interaction between a matrix prismatic < c > edge dislocation and a migrating (10 (1) over bar2) twin boundary results in extended basal < a > mixed dislocations in the twin lattice. The interaction between the resultant < a > dislocation and the migrating twin boundary is studied using molecular dynamics simulations. The < a > dislocation tends to detach from or connect to the twin boundary, when its slip plane intersects a compression or extension site of the twin boundary. When the < a > dislocation connects to the twin boundary, connection always occurs with a 90 degrees Shockley partial and a basal-prismatic (BP) or prismatic-basal (PB) two-atomic-layer-height step, depending on whether the Burgers vector direction of the Shockley partial points away from or towards the twin boundary. The BP or PB two-atomic-layer-height step is sessile, in contrast to those that are not connected to such < a > dislocation.